We are using an encryption appliance that is capable of creating S/MIME certificates for internal users. The appliance is synchronizing with AD to get the user. When the certificate is created it will contain all users smtp mail addresses configured on Exchange for this particular user.
Later e-mail addresses do NOT appear in certificate
After the certificate is created and we add another mail address for the same user we can see that the mail address is added as a property for the user account on the appliance but the certificate is not changed. I was thinking maybe it's by design that it's not possible to modify an existing S/MIME certificate (tried to find something in RFC's but without luck).
I think it's the value that is controlling it
X509v3 Subject Alternative Name: email:firstname.lastname@example.org, email:email@example.com,